An official website of the United States government
Four small coastal moorings were deployed in water depths of ~5-6 meters (m) on the Colville Delta front and one site farther west for a period of approximately one week in Jul/Aug 2021. Moorings were outfitted with sensors to collect a variety of data including water levels (at all sites), turbidity/total suspended solids, water velocity, salinity, temperature, and light intensity. Light intensity measurements were also collected from a vessel-mounted sensor (included in the MM3 data package) to allow for calculation of light attenuation at the mooring. These data are described more fully in a companion publication (Eidam, "Summertime water and particle properties on an ice-influenced Arctic shelf", in prep as of March 2025).
more »
« less
Mooring data from Harrison Bay, Alaska, August-September 2022
Six small coastal moorings were deployed in Harrison Bay for approximately 30 days between early August and early September. Two moorings were outfitted with Nortek Aquadopps and optical backscatter sensors and the remainder were outfitted with RBR sensors which recorded some combination of salinity, temperature, pressure, and turbidity. All sensors were mounted within approximately 0.5 meters (m) of the bed to capture boundary-layer dynamics. Turbidity values were converted to total suspended solids concentrations. Wave parameters (significant wave height, peak wave period, and wave direction) were post-processed from Aquadopp data. Shear velocities (used in sediment-transport research) were calculated from current and wave data at the sites where Aquadopps were mounted. Data have been used in support of a publication, "Summertime sediment convergence on the Alaskan Beaufort Shelf and implications for ice rafting."
more »
« less
- PAR ID:
- 10635162
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Mooring, salinity, temperature, pressure, velocity, turbidity, total suspended solids, wave parameters, shear velocity, shear stress
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Introduction The National Science Foundation Ocean Observatories Initiative (OOI) collects continuous in-situ measurements of dissolved oxygen (DO) on the Endurance Array moorings in the inner shelf region of the Oregon and Washington coasts. Aanderaa Optode 4831 oxygen sensors were deployed at 7 meters depth on the near surface instrument frame (NSIF) and on the collocated coastal surface piercing profiler (CSPP) moorings. The sensors suffer from calibration drift due to biofouling, which can cause a dramatic increase in DO during daylight hours and corresponding decrease at night compared to the conditions in the water column (Palevsky et al., 2023). This enhanced diel signal, when present, is much more pronounced on fixed-depth sensors and usually begins to occur 1-2 months after a mooring is deployed. After this biofouling issue was identified, OOI began deploying UV lamps adjacent to the oxygen sensor in spring 2018, after which there was substantial improvement in DO data quality. Each file in this dataset contains the measured near surface DO and the corrected near surface DO at the Oregon and Washington inner shelf surface moorings (ISSM) with gaps from periods of biofouling replaced with the DO measured by the CSPP. Methods OOI oxygen data Dissolved oxygen sensors on OOI CSPPs and at fixed-depths on moorings are named “DOSTA”, a contraction of DO Stable Response. The DOSTA data are downloaded on a deployment-by-deployment basis for all available data streams (telemetered and recovered for fixed-depth moorings; recovered only for CSPPs) from the OOI Gold Copy THREDDs catalog. Each deployment file additionally contains the practical salinity, seawater temperature, and pressure measured by the collocated CTD. The telemetered and recovered data streams are combined and interpolated to a common timebase with one-minute resolution. Evaluate fixed-depth oxygen data The NSIF DO data are quality-controlled using both automated and manual methods to create flags that follow the Quality Assurance of Real-Time Oceanographic Data (QARTOD) standards. Endurance array team members perform a visual inspection of oxygen and ancillary data from each deployment to determine instrument failure from biofouling or other issues. Annotations from human-in-the-loop analyses of failed or suspect data generate the QARTOD flags. Merge profiler oxygen data QARTOD flags are applied to the CSPP data to omit failed data points. CSPP DO data are averaged from 2-7 meters depth then interpolated to the one-minute timebase. The resulting CSPP time series shows good agreement with the NSIF during data overlaps. Finally, the NSIF DO data is replaced with the CSPP DO data during periods of biofouling or instrument failure, flags are generated for the hybrid DO dataset, and separate netCDF files are created for the Oregon and Washington locations. Files Filename: CE01ISSM-NSIF-DOSTA.nc Description Oregon Coastal Endurance Site CE01, Inner Shelf Surface Mooring, Near Surface Instrument Frame, Dissolved Oxygen Stable Response Geographic Range Latitude: 44.6598 to 44.6598 Longitude: -124.095 to -124.095 Time Range Start: 2014-10-10, 18:00:00 UTC End: 2025-06-24, 20:00:00 UTC Variables: "time", ”depth”, "sea_water_practical_salinity", "sea_water_practical_salinity_qartod_results", "sea_water_temperature", "sea_water_temperature_qartod_results", "measured_dissolved_oxygen", "measured_dissolved_oxygen_qartod_results", "corrected_dissolved_oxygen", "corrected_dissolved_oxygen_qartod_results" Filename: CE06ISSM-NSIF-DOSTA.nc Description Washington Coastal Endurance Site CE06, Inner Shelf Surface Mooring, Near Surface Instrument Frame, Dissolved Oxygen Stable Response Geographic Range Latitude: 47.1336 to 47.1336 Longitude: -124.272 to -124.272 Time Range Start: 2015-04-10, 05:00:00 UTC End: 2025-06-24, 20:00:00 UTC Variables: "time", ”depth”, "sea_water_practical_salinity", "sea_water_practical_salinity_qartod_results", "sea_water_temperature", "sea_water_temperature_qartod_results", "measured_dissolved_oxygen", "measured_dissolved_oxygen_qartod_results", "corrected_dissolved_oxygen", "corrected_dissolved_oxygen_qartod_results"more » « less
-
This dataset includes water-column data collected from the Beaufort Shelf during the open-water seasons in 2020, 2021, and 2022. The 2020 data include water-column profiles (salinity, temperature, depth, turbidity, particle size distributions, particle volume concentrations, and uncorrected clorophyll-a) collected with an RBR CTD/Tu (conductivity, temperature, depth, turbidity) sensor and LISST sensor from R/V Sikuliaq and its workboat. Most sites were in the Harrison Bay region (north of the Colville Delta and Simpson Lagoon) and a few were located farther east. The 2021 and 2022 data include the same CTD/Tu and LISST data that were collected in 2020, but are focused in Harrison Bay and also include profiles of light intensity (photosynthetically active radiation) as well as ADCP (acoustic doppler current profile) profiles from a pole-mounted Nortek Signature 500 kilohertz (kHz) sensor. In 2021, additional data include filtration data (total suspended solids, suspended sediment concentrations, and organic fractions) from water samples and hi-resolution echosounder data from the Nortek ADCP. These data are being incorporated into publications about summertime water-column properties and sediment transport dynamics within Harrison Bay (Eidam et al., pending).more » « less
-
null (Ed.)Turbidity currents deliver sediment rapidly from the continental shelf to the slope and beyond; and can be triggered by processes such as shelf resuspension during oceanic storms; mass failure of slope deposits due to sediment- and wave-pressure loadings; and localized events that grow into sustained currents via self-amplifying ignition. Because these operate over multiple spatial and temporal scales, ranging from the eddy-scale to continental-scale; coupled numerical models that represent the full transport pathway have proved elusive though individual models have been developed to describe each of these processes. Toward a more holistic tool, a numerical workflow was developed to address pathways for sediment routing from terrestrial and coastal sources, across the continental shelf and ultimately down continental slope canyons of the northern Gulf of Mexico, where offshore infrastructure is susceptible to damage by turbidity currents. Workflow components included: (1) a calibrated simulator for fluvial discharge (Water Balance Model - Sediment; WBMsed); (2) domain grids for seabed sediment textures (dbSEABED); bathymetry, and channelization; (3) a simulator for ocean dynamics and resuspension (the Regional Ocean Modeling System; ROMS); (4) A simulator (HurriSlip) of seafloor failure and flow ignition; and (5) A Reynolds-averaged Navier–Stokes (RANS) turbidity current model (TURBINS). Model simulations explored physical oceanic conditions that might generate turbidity currents, and allowed the workflow to be tested for a year that included two hurricanes. Results showed that extreme storms were especially effective at delivering sediment from coastal source areas to the deep sea, at timescales that ranged from individual wave events (~hours), to the settling lag of fine sediment (~days).more » « less
-
Abstract Sensor‐based, semicontinuous observations of water quality parameters have become critical to understanding how changes in land use, management, and rainfall‐runoff processes impact water quality at diurnal to multidecadal scales. While some commercially available water quality sensors function adequately under a range of turbidity conditions, other instruments, including those used to measure nutrient concentrations, cease to function in high turbidity waters (> 100 nephelometric turbidity units [NTU]) commonly found in large rivers, arid‐land rivers, and coastal areas. This is particularly true during storm events, when increases in turbidity are often concurrent with increases in nutrient transport. Here, we present the development and validation of a system that can affordably provide Self‐Cleaning FiLtrAtion for Water quaLity SenSors (SC‐FLAWLeSS), and enables long‐term, semicontinuous data collection in highly turbid waters. The SC‐FLAWLeSS system features a three‐step filtration process where: (1) a coarse screen at the inlet removes particles with diameter > 397 μm, (2) a settling tank precipitates and then removes particles with diameters between 10 and 397 μm, and (3) a self‐cleaning, low‐cost, hollow fiber membrane technology removes particles ≥ 0.2μm. We tested the SC‐FLAWLeSS system by measuring nitrate sensor data loss during controlled, serial sediment additions in the laboratory and validated it by monitoring soluble phosphate concentrations in the arid Rio Grande river (New Mexico, U.S.A.), at hourly sampling resolution. Our data demonstrate that the system can resolve turbidity‐related interference issues faced by in situ optical and wet chemistry sensors, even at turbidity levels > 10,000 NTU.more » « less
